Most research-compound suppliers will tell you their products are tested. Fewer will tell you who did the testing. That single detail decides whether a Certificate of Analysis is evidence or marketing.
The problem with self-certification
A supplier-provided COA is produced by — or on behalf of — the company selling the compound. Often it is simply the manufacturer's own document, passed along. This is the analytical equivalent of grading your own exam. The party with a commercial interest in the result is the same party reporting it.
That does not make every supplier COA wrong. It makes every supplier COA unverifiable by an independent standard — and in research, unverifiable is the same as unknown.
What independent testing means
An independent third-party COA is produced by a laboratory with no financial relationship to the supplier or the manufacturer. The lab has no stake in the outcome, no influence over the method, and no reason to report anything but the measured result.
This is the G13 standard. Every batch is submitted to an independent third-party laboratory for HPLC analysis before release. G13 does not self-certify and does not rely on manufacturer-provided results.
How to tell the difference
- Is the COA tied to a specific lot number you can look up?
- Is it published openly, or only sent on request?
- Does it state the testing method?
- Can you verify the exact batch you received — not a representative sample?
G13 answers yes to all four. Every batch is publicly verifiable in the COA Portal, and every order is lot-matched. Read more about the verification-first standard behind it.